Axle Riser/Lift Kit

Greetings:

I've owned 2 pods, a 171 and now a 2015 179.  I have had the factory lift kits on both.  I have driven many miles on rough 2 lane roads in MN and WIS plus gravel and hayfields for dry camping.  I've had no problems with the frame or axle on either pod. I try to avoid running over curbs etc. but have at very low speeds.  I have dual LP tanks and a group 27 battery, and usually a full tank of water.  Several pod owners have gone to Alaska and back with pods.  I do think the axle is a bit light.  I've looked at some other RV's similar to the pod that had frames with smaller square tubing.  I wonder how they work out.  

Crankster78

a 2x5x0.1 tube is 74% stronger in bending than a 2x4x0.1 tube so without having done all the detailed equations for the 195 I think it's frame would probably be no worse if not better than a smaller rPod's.  

All this material is going to be fabricated from mild steel for cost reasons so there isn't any reason to be concerned about the strength of the lift kit compromising the frame because of that. The lift kit does add to the stress on the frame from hitting a curb or from hard braking, see my post above.  

The lift kit won't add more force but it will add more moment (think torque). The vertical load on the frame from gravity or from getting lifted by a bump or dropping into a hole won't change.  The moment from the arm of the torsion axle getting pushed up also won't change. What will change is the moment caused by braking or by hitting a curb. That is because torque is force x distance. The distance is the height difference between the contact patch and the frame, which is increased by the lift kit. If it helps to visualize this imagine the extreme case where you bolt 10 foot stilts on your trailer and then you run it into a curb. The stilts would act as a long lever and immediately twist the frame where it is attached.

Is it a significant increase? With my lift kit the distance from the contact patch to the frame is 14 inches. Without it it would be 10.5 inches, so it adds 33% to the stress on the frame from braking or hitting a curb. So yes it is significant. 

Is it enough more to cause a frame failure? The only reported frame failure I know of is Olddawgsrule's and he doesn't have a lift kit on his trailer. There are lots of owners who have lift kits, including all the HRE's until FR started increasing height by changing the start angle on the torsion arm, not sure when that was. So I'd say that there is no hard evidence that adding the lift kit increases the stress on the frame enough to cause frame failures in the real world. 

For me, if I can come up with a simple and inexpensive way to reinforce the frame at that weak point I will just do it rather than risk a failure, but I'm not giving up my lift kit.  For where I camp the standard height trailer is just too low to the ground.